This is a major step forward for the leading provider of cloud services in that the company is not only offering enterprises an alternative to running compute and storage infrastructures in their own datacenters but now Amazon is using its cloud infrastructure to become a major software-as-a-service (SaaS) distributor.

Amazon customers can rent applications by the hour or by the month and run them on the AWS portfolio of cloud services and pay for them on the same bill. Already on board are well-known players such as 10gen, CA, Canonical, Couchbase, Check Point Software, IBM, Microsoft, Red Hat, SAP and Zend, as well as open source purveyors Wordpress, Drupal and MediaWiki, said Amazon CTO Werner Vogels, in a blog post.

The move is the latest effort by Amazon to extend the breadth of its enterprise cloud offerings and its reach. Just yesterday, Amazon launched a new partner program that it plans to roll out this year, aimed at certifying ISVs, systems integrators and consultants. In addition to distributing apps from major software providers, Vogels underscored it will democratize the distribution of wares from lesser-known developers.

"The way businesses are buying applications is changing," Vogles said. "There is a new generation of leaders that have very different expectations about how they can select the products and tools they need to be successful. It has had a true democratization effect; no longer does the dominant vendor in a market automatically get chosen."

The products are distributed as Amazon Machine Images (AMIs), which run on EC2 instances. Customers can search for products, which are each described by a "detail" page, which provides information such as an overview, ratings, versioning data, support offerings and a link to the end user license agreement (EULA) as well as pricing.

Mimicking the "Click-to-Buy" model of its online consumer store, users can "Click-to-Launch" applications in the AWS Marketplace. "We've streamlined the discovery, deployment, and billing steps to make the entire process of finding and buying software quick, painless, and worthwhile for application consumers and producers," wrote Amazon Web Services technical evangelist Jeff Barr, on the AWS blog.

Certainly Amazon is not the first to launch a marketplace selling software for enterprises. But given its footprint as growing presence as a provider of cloud infrastructure, not to forget the huge success of its consumer retail site, Amazon could become could become a key player in the sales and procurement of enterprise apps, dev tools and infrastructure.